The most obvious use of the earlobe in man is for piercing and holding
earrings. Earlobes seem to have a much longer history for piercing than
other parts of the anatomy although the growing practice of piercing other
parts of the anatomy seems to be surpassing the use of the earlobe!
It is unlikely that we evolved the earlobe for purposes of piercing. In
reality, there is no known biological function associated with the earlobe
in man. This small piece of flesh does have a prominent blood supply but
it does not contain cartilage like the other parts of the external ear.
The most obvious difference among humans is that the lobe is attached to
varying degrees to the side of the face. Some of us have an earlobe that
is more like an appendage while in others the lobe is more directly
attached.
Some muscles attached to the external ear in humans seem vestigial in terms
of evolution. Some of us can wiggle our ears, some of us cannot. In lower
mammals, dogs for instance, these muscles allow exquisite control of the
external ear for purposes of moving them to better able to detect where
sounds originate. In some aquatic animals, the little tab of skin in front
of the ear canal, called the tragus, can be operated to act as a valve to
open and close the ear canal.
However, the earlobe itself has no known biological function.